1. Field of the Invention
The present invention generally relates to a lubrication system for land vehicles. More specifically, the present invention relates to an improved lubrication system for snowmobiles that can be accommodated in a smaller engine compartment.
2. Description of the Related Art
A snowmobile is a land vehicle that is propelled by a drive belt generally centered on a vertical longitudinal central plane. A pair of snow skis are arranged generally forward of the drive belt at locations generally laterally off-set on either side of the vertical longitudinal central plane. An internal combustion engine is coupled to the drive belt to drive the snowmobile over uneven terrain, sometimes at relatively high speeds. The snowmobile engine is generally mounted within a substantially enclosed engine compartment forward of the rider's seat. The engine compartment typically is defined within a cowling and is generally relatively small.
The snowmobile engine has a lubrication system that reduces friction between the moving parts of the engine and thereby reduces heat that is generated by friction during the operation of the engine. Many such engines are dry-sump engines. In other words, the lubrication system of the engine includes a lubricant tank that stores the lubricant that is not circulating through the engine. The lubricant tank is generally positioned within the engine compartment at a location forward of the engine. Unfortunately, locating the lubricant tank forward of the engine requires a larger engine compartment to house the engine and the lubricant tank.
In addition to being mounted longitudinally forward of the engine, the lubricant tank usually has a short and wide profile. In other words, the height (i.e., the vertical dimension of the lubricant tank) is small compared to the longitudinal horizontal dimension (i.e., the dimension of the lubricant tank along a line in or parallel to the vertical longitudinal central plane) and the height is small compared to the transverse horizontal dimension (i.e., the dimension of the lubricant tank along a line transverse, or perpendicular to the vertical longitudinal central plane). Stated another, way, the horizontal cross-sectional area of the lubricant tank is relatively large while the vertical cross-sectional area of the lubricant tank is relatively small. This is disadvantageous because lubricant sloshing caused by the uneven terrain and relatively high speed of the snowmobile can cause air to be entrained with the lubricant, which degrades the performance of the lubrication system.